Real Time Clock

DS1307N
64 X 8 Serial Real Time Clock
FEATURES
♦ Real time clock counts seconds, minutes, hours, date of the month, month, day of the week, and year with leap year compensation valid up to 2100
♦ 56 byte nonvolatile RAM for data storage
♦ 2-wire serial interface
♦ Programmable squarewave output signal Automatic power-fail detect and switch circuitry
♦ Consumes less than 500 nA in battery backup mode with oscillator running
♦ Optional industrial temperature range -40°C to +85°C
♦ Available in 8-pin DIP or SOIC
♦ Recognized by Underwriters Laboratory
ORDERING INFORMATION
DS1307 8-Pin DIP
DS1307Z 8-Pin SOIC (150 mil)
DS1307N 8-Pin DIP (Industrial)
DS1307ZN 8-Pin SOIC (Industrial)
DESCRIPTION
The DS1307 Serial Real Time Clock is a low power, full BCD clockcalendar plus 56 bytes of nonvolatile SRAM. Address and data are transferred serially via a 2-wire bi-directional bus. The clockcalendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with less than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with AMPM indicator. The DS1307 has a built-in power sense circuit which detects power failures and automatically switches to the battery supply.
DS1307 BLOCK DIAGRAM Figure 1